Fluid-pressure-operated chuck.



PATBNTBD MAY '19. 1903..

B. M. W. HANSON. FLUID PRESSURE OPERATED CHUCK.

APPLIoATIoH FILED JAN. 15. 1902.

` 2 SHEETS-SHEET 1.

No Monm..

wwwm@ Wil/1115566.- /-J v PATENTED MAY 19, 1903.. B. M. W. HANSON. PLUIDPRESSURE OPERATED CHUCK.

APPLICATION FILED JAN. 15. 1902.

2 SHEETS-SHEET 2.

NO MODEL.

UNITED STATES Patented may 19, 190s.

v'PATENT OFFICE.

. BENGT M. W. HNSON, OF HARTFORD, CONNECTICUT, ASSIGNOR TO PRATT t WHITNEY COMPANY, OF HARTFORD; CONNECTICUT, A CORPORATION OF NEW JERSEY.

SPECIFICATION forming part of Letters Patent No. 728,458, dated May 19, 1903.

Application filed January 15. 1902. Serial No. 89,874. (No model.)

To ail whom traag concern:

Be it known that I, BENGT M. W. HANsoN, a citizen of Sweden, and a'resident of Hartford, in the county of Hartford and State of Connecticut, have linvented certain new and useful Improvements in Fluid-Pressure-Operated Chucks,`of which the *following is a specification.

This invention is an improved chuck or work-gripping device especially adapted for rotation and adapted to be operated during rotation v'at any desired speed Without imposing any thrust orfrictional resistance to the bearings uponV which the chuck may be mounted.

The embodiment of my invention herein Ashownis adapted for use in connection with -which is moved longitudinally of the spindle *t to open and close the collet or chuck by means of a non-rotating clutch-fork operated by a hand-lever in case of `a hand-operated machine or by means of acam in case of an auspindle m-ust'besustained by means of thrusttomatic machine. -The longitudinal thrust, which is usually quite considerable, being thus applied by a member extraneous to the .4 collets of the spindle bearing against stationaryI thrustbearings, thus causing a correspondingamount of friction'al resistance to the rotations of the spindle. The same frictional resistance to rotation also occurs at thebearing between. the clutchfork and the cone which it operates. In other words, the4 power applied to rotate the spindle must be increased beyond the amount necessary'to do the required work by the amount necessaryto overcome the friction due to operating the chuck from an extraneous non-rotating member, and that friction is doubled by being applied, first, at the clutch-fork, and, second, at the counteracting thrust-bearings of the spindle. In this invention thesethrusts and the consequent resistances are avoided 4by operatihg the chuck directlyby means of -fluid-pressure mechanism carried with or appurtenant to the spindle or chuck itself without any extraneous thrusts or resistances, and therefore requiring for the rotation of the spindle and chuck only the amount of power required to: perform the actual operations upon the work. I

Figure 1 of the drawings is a side View, in

shown is mounted in a frame or head 8, which may be attached to or integral with the frame of. the lathe, screwmachine, or other maf chine with which the apparatus is to be employed. For convenience of manufacture and assembling this apparatus isA made in several parts, -which when assembled constitute two. principal structures which rotate together; but one of them is moved longitudinally of the other by the pressure devices employed in order to operate the chuck to grip and release the work. One of these Ytwo parts is provided with a cylinder and the other part with a'piston working in 'the cylinder,

so that when one of the saidprincipal'parts is held against longitudinal movement the l pressure devices operate the free or movable part. In the present embodiment the parts 'provided with a piston are held against longitudinal movement, while those attached to the cylinder are moved longitudinally by the pressure, the `piston being connected with the collet or jaws for closing upon the Work, while the cylinder is connected with means for closingthe jaws or collet. The movable parts consist of the hollow spindle 1'0, mounted in suitable bearings in the frame 8, the

forward end of the spindle being adapted to the chuck-jaws or collet'upon the work.

engage with and .close the jaws of the collet. This spindle has the cylinder 11 fixed upon it by means of the screws 12. The cylinder may alsoserve, as herein shown, as a pulley or gear for imparting rotary movement to the chuck, and its left-hand or rearward end is adapted, as will be more fully described, to receive the air-pressure employed for operating the piston.

The chuck herein shown is of a well-known simple-form, comprising a spindle and a split collet. The collet 13 is bored or ground out tothe nominal diameterof the work and split lengthwise to form the jaws, which are clamped upon the work. 'lhe outer end of the col-let is tapered and tits in acorre'spondingly-tapering seat in the fro`nt end of the spindle 10, so that by moving the spindle or the collet 1 3 longitudinally with relation to each other the rodv 15 or any other work or tool may be gripped or released. The cylinder and the piston form abutting or opposing parts for applying the pressure to effect the longitudinal movement of the movable mem-v berv in one direction to operate the chuck and should be of sutcient area; for the eect-ive use of fluid-pressure, these members being also utilized herein for the application of the pressure of one or more springs which here operate in the opposite direction for closing In machines of this class it is customary to push the work forward, either manually or automatically, vagainst a stop, the collet being loosened for this purpose. Where, as is the usual practice, the collet is moved longitudinally to grip the work, it is evident that the latter is also moved longitudinally from the position to which it has been set t-o an extent "varying with the variationsv in diameter of the work. The well-'known practical effect of this is that varying lengths of the work are presented to the tools which operate upon it, so that it is difficult to produce finished work of uniform length from bars or rods of stock which vary to 4any appreciable extent in diameter, or which are not perfectly uniform in cross-section, or which are covered in any degree with dirt or scale. To obviate this diliculty, I preferablyv maintain the collet 13 in a constant longitudinal position by means of the thrust-collars 16 and 17 appurtenant to that collet, those collars engaging with a suitable flange or collar 18 of the frame 8 and hereinshown to be attached to that frame by means ot'l screws 19. For the adjustment of this thrust-bearing I providel theadditional screw collar 20, which is clamped to place when the bearing is prop'- erly adjusted.

A1n order to enable the collet 13 to be readily removed andcollets ofother sizes inserted and for the purpose of enabling these collets to be accurately adjusted to longitudinal po sition for effectively gripping the work, the collet itself does not extend integrally through to its thrust-collarsl and 17, but is preferably provided with an extension or plunger 14, to which the collet is attached in any convenient way, as by means of the screw-thread shown in Fig. 1. The colletand its plunger both rotate with the main spindle 10, the collet being vkeyed to that spindlel by means of the key 21 engaging with a longitudinal keyway in the collet 13, which permits the lon-v gitudinal movement of the latter. The key 21 is preferably provided with a cylindrical stem, .which fits a corresponding drilled hole in thev main spindle 10. The collet-plunger 14 is made to rotate with the main spindle 10 by means of the key 22, and in order to enable the plunger to be readily unscrewed from the collet provision is made for readily re-4v tracting the key 22. made to extend outwardly through the hub of the pulley 11 and is provided with a spring y 23, which holds it yieldingly into its` keyseats 26 in the plunger 14. The stem of the key is provided with a spring-detent 24, (shown in Figs. 1 and 4,) which engages in a recess 25 inthe side of the pulley 11 'and' is provided with a series of key seats or.

notches 26, arranged around the periphery of the plunger, as best shown in Fig.,4. For convenience of construction andass'embling, the piston 28 is mounted upon theoutside of the spindle 10 and is connected with the plunger 14 by means of one or more segmental thrust-blocks 29. (Best shown in Figs. 1 and 3.) These blocks are herein shown to be two in number and are seated upon diametrieally opposite sides of the plunger 14, in an annular groove turned therein, forming annular shoulders, by means of which the longitudinal thrust of the pressure against the piston is sustained by the plunger 14. The peripheral portions of these blocks tit in the internal annular groove 30 in the piston 28, and they are secured thereto by means of the screws 31. 'lhe shell of the spindle 10,which intervenes between the piston 28 and the plunger 14, is slotted, as shown at 32 in Figs. 1 and 3, to permit the required longitudinal movement of that spindle relative to the colv let-plunger, these slots serving as splineways for the blocks,whereby the piston 28 is, maintained in constant rotative relationl to the spindle 10 and the pulley 11.

To this end that key is ICO IIO

In order to facilitate the assembling of the ,j

parts, and particularly to enable the seg.

mental key-blocks 29to be readily inserted, the piston l1 is slotted on opposite sides, as at 33, from the groove 30 to the end of the hub, as best shown in Fig. 6, forminga bayonet-lock for the entrance of the blocks from the end of the hub into the grove 30. The blocks may then be placed in position through the slots 32 of thespindle 10 and into Ithe groove of the plunger 14. The piston can thenbe pushed over the blocks by .bringing the slots-33 into coincidence with the blocks.

'When the piston is pished far enough to bring theblocks into coincidence with the annular groove 30, the piston is turned until the blocks are substantially at right angles to or at least out of coincidence with the slots 33, as shown in Fig. 3. The screws 31 are then inserted, openings being left through the periphery of the pulley 11 for thisl purpose, those openings being afterward closed by means of the screw-plugs 34.

The piston 28 is preferablyas here shown, entirely inclosed within the pulley l1, which -is made separable at 35 to facilitate the construction and assemblingof the parts. With thisv general construction andarrangement either the piston or the pulley may be moved longitudinally to operate the chuck according as the end-thrust bearing is applied to the main spindle or the collet-plunger 14. For the reasons hereinbefore stated I prefer to apply that thrustbearing to the colletplunger, as herein shown, thereby holding the piston against longitudinal movement Iand moving the cylinder longitudinally.

portioning the size, length, number, and

In the embodimentherein shown the pressure of springs is utilized to close the collet, and the pressure of compressed air or other Huid-pressure is employed to release the collet, as will now be more fully'described. The

front face of the piston 28and the adjacent inner face of the pulley 11 are provided with a spring or withatseries of springs 38, ar-

ranged at substantially equal distances around the spindle, so as to apply the pressure uniformly. The pressure of these springs tends to move the pulley and Iits main spindle lO toward the right to grip the collet, as

shown in Fig. 1, and as these springs abut against the piston,which is connected withthe collet, the strains of operating theehuck are all contained within the rotating parts, so as to cause no frictional resistance whatever to the rotations of the spindle. By suitably provamount of compression of these springs almost any desired pressure can be obtained Withoutinvolving any stress or friction outiside of the spindle and the other rotating parts. l

. annular passage 45 in the face of the collar 40, which annular passage communicates at all times with the lateral port 46, leading to the annular clearance-space 47 between the operations upon the work.

rearward face of the. piston 28 and the adjacent inner wall of the pulley 11.

In order to permit the feed-tube 43 to follow the longitudinal movement of its supplycollar 40 and its associated parts, that tube is connected with the supply-opening 48 by means of an intervening telescopingyoke 49, the passages of which are arranged to permit. free communication between the su pply-inlet 48 and the feed-tube 43 at all positions of the latter. The duid -pressure is conducted to the inlet 48 in any desired or convenient way, suitable valves being employed to control the admission and exhaustionV of the pressure. These controlling valves may be operated either manually by the attendant or they may be automatically controlled by cams or other devices/ in proper time and relation to the other operations of the machine with which this apparatus may be employed.

It will be obvious that the 'Huid-pressure devices which are herein shown to be applied to" one side of the piston 28 for releasing the collet may also be applied to the other side of that piston for closing the collet, thus dispensing with the springs 38 and operating the` lcollet in both directions by means of uidpressure, or the application herein shown may be reversed and the springs employed for opening the collet, the air-pressure being Vemployed for closing the collet. This may be position, to grip and carry the Work especially where it is desirable, 'as in most cases, to

economize in the use of'the fluid-pressure, which in such an arrangement wouldbe employed only during the short period requiredv for opening the chuck and moving the vwork` forward, and would be shut oi `during the much more extended time that is usually required AforV performing the cutting or other Various forms of well-known devices may be employed for advancing the work when the collet is'loo'sened, either automatically or otherwise. When arranged to operate automatically,theWork-advancing devices should obviously be timed in coincidence with the loosening of the collet,`as in the case of the well-known automatic screwmachine now` operated by mechanical contrivances. y

If for any reason it should be found objectionable to movethe cylinder 1p1-and its main spindle 10 longitudinally, the longitudinal movement may be impartedl to the colletby applying thrust-collars to the spindle 10 upon opposite sides of` one of its bearings or by 1n- IOO rsa

serting a thin collar-between the front end of the hub of the pulley and the face of the adjacent bearing and employing either a solid or a detachable collar` upon the spindle 10 adjacent to the front face of that bearing. Then by removing the thrust-collars 16 and 17 of the collet-plunger or the cooperating fiange 18 of the head the collet and its attached piston 28 will then move longitudinally of the spindle and operate the collet'. In many ways well known to those familiar with this art the invention herein shown may be modified and its applications greatly extended.

I claim as my invention- 1. The combination of a head or frame, a rotatable spindle journaled thereon, a Workgripping collet extending. axially within the spindle and provided with thrust-collars engaging with the head or frame to prevent lonconnectedv with the collet and with the spin. l dle, respectively.

x V2. The combination of a head or frame, a rotatable spindle journaled thereon, a workgripping collet carrie'd by the spindle and provided with thrust-collars engaging with the -head er frame to prevent longitudinal movement of the collet, and a fluid-pressure cylinder and piston 'carried by the spindle and means for connecting the piston and the collet through the'shell-ot the spindle.

3. The combination of a head or frame, a rotatable spindle journaled thereon, a workgripping collet extending axially through the spindle, and provided with thrust-collars ento rotate therewith,means for connecting the piston with the collet through the shell of the spindle, a spring device interposed between the cylinder and one side of the piston, and

means for admitting duid-pressure to the,

cylinder at the opposite side of the piston to overcome .the pressure of the spring device.

4. The'combination of a rotatablekspindle, awork-gripping collet carried by the spindle, and extending axially therein, a pressurecylinder mountedv upon and rotating with the spindle, a piston within the cylinder provided withthrust-blocks passing through the wall of the spindle, and engaging with the collet, means for applying spring-pressure to effect the relative longitudinal movement of' the spindle and collet in one direction, and means for applying fluid-pressure to the piston to overcome the pressure of the spring and effeet the said relative movement inthe eppo-` site direction.

5. The combination of a rotatable spindle,

a collet carried thereby, and extending exi-- ally therein, a piston for duid pressure mounted upon the spindle, and provided with a circumferential seat for a thrust-block, and

having a longitudinal slot for admitting'the thrust-block toits seat, a thrust-block located in said seat, and extending through lthe wall ot`l the spindle into engagement with the collet, means for applying t spring-pressure to eiect the rotative longitudinal movement of the spindle and collet in one direction, and.

7. The combination of a rotatable spindle,'

a workgripping collet carried by the spindle, a plunger connected with the collet by a screwthread and mounted axially within the spindle, and provided with a circumferential series of detent-notches, means for preventing relative rotation of the collet and the spindle, a retractable key carried by the spindle for engaging with the detenta-notches of the plun ger, and a fluid-pressure cylinder and piston carried by the spindle, the piston being connected with the plunger by means of a thrustgrippingchuck, a fluid-pressure engine rotating with the chuck, and means for transmiting iuid-pressu re tothe engine, comprising a no n-rotating collar, mounted between shoulders of the chuck, and provided with an inlet for the pressure, the collar being also provided with annular passages, communicating with the inlet and opening with equal areas upon its opposite sides, against the said shoulders of the chuck, one of the said 4annular' passages communicating with the pressurespace of the engine, andan adjustable collar for taking up the wear and preventing leakage of the pressurev fluid.

10. In combination with a rotatable workgripping chuck, afluid-pressure engine rotating with, and for operating the chuck, and means for transmitting fluid-pressure to the engine, comprising a non rotating collar mounted between the shoulders of the chuck, dinally against the non-rotatin g collar to take xo and provided with an inlet for the pressure, up the wear and prevent leakage of the presand provided with annular'passages around sure. u

the side faces of the collar, and opening with Signed at Hartford, Connecticut, this 11th equal areas upon its opposite'. sides against day of January, 1902. the said shoulders of the chuck, one o f the 4 BENGT M. W. HANSON. said annular passages communicating with` s Witnesses: the pressure-space of the engine, vand one of p F. V. ABAR'rLiznT,

the said shoulders being adjustable longitu- WM. H. HONISS. 

